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The JC 1 breaks new ground in parts quality, as there is nothing in high end audio that approaches the
quality of parts we chose -“ reflecting many years of our continuing parts research and evaluation.
The JC 1 also breaks new ground for circuit boards which allows such attributes as focus, speed and
immediacy to shine through due to the highly unusual, very tight layouts Carl designed. Some of the
outstanding high performance parts are as follows:
- Vampire Direct gold-plated OFC RCA jacks
- Neutrik XLR connectors
- Reliable RT DC bypass and Zobel capacitors
- Superior Electric binding posts
- Vampire continuous cast copper signal and DC wiring
- Nichicon Great Supply raw DC capacitors (132,000uF in the high current supply)
- Nichicon Muse DC and local bypass capacitors
- Harris hyperfast soft recovery diodes for all bridge rectifiers
- Sanken output transistors - the most powerful complementary transistors available
The JC-1 delivers 25w in class A allowing most amplification to be contained within the class A mode
except for large bass transients. The unit uses separate power supplies for the input/driver section
allowing the JC-1 to be totally immune to fluctuations in the AC line voltage. We did the best we could
with the electrical design, layout and parts selection/voicing and were confident the JC 1 will
surpasses virtually every other amplifier on the market regardless of price.
Bob Crump
Carl Thompson on the JC 1 Layout
The real challenge in the JC 1 project was to take Johns subtle and elegant circuits, Bobs well-
considered parts selections, and implement everything in an uncompromised, cost-effective manner,
without the performance sacrifices usually associated with other than astronomically priced equipment.
Circuit functions were divided between four separate, carefully oriented circuit boards (and associated
wiring) to minimize unwanted circuit interactions. Overall, system signal flow was developed in concert
with the board layout with special emphasis on overall system grounding. Boards underwent many
layout iterations both to optimize manufacturability and performance. The final main board can handle
double the very, very substantial current of which the JC 1 is capable. This required very wide
matched circuit paths in 2 oz. copper on both sides of the board for critical nodes.
The JC 1 is very difficult to stress so that audible strain due to layout-generated resistance will be
vanishingly small. Part of the reason for such a beefy layout is the huge power supply which required
fitting four very large filter capacitors plus the separate input stage power supply on the main circuit
board. The separate dedicated input board is thus more immune to power supply noise and from
circuit noise in the separate auto turn on control board. The JC 1 input board mounts directly on the
back panel for minimum input and input select wiring length. The layout is absolutely symmetrical with
the minimum possible signal path. Here too, theres an emphasis on minimum resistance to reduce
unwanted circuit interactions.
Ive only occasionally said of the design of highly refined equipment that it starts to glow after a
certain point. Its when you know that there are virtually no unquestioned design elements and there is
a deceptive simplicity and wholeness to the overall package that is apparent to the practiced eye. The
JC 1 glows.
Carl Thompson
Parasound Products, Inc. 950 Battery Street, San Francisco, CA 94111
415-397-7100 / FAX 415-397-0144 www.parasound.com
